In order to facilitate drilling with manual powerful rock drill machines, a feed leg is used to support the rock drill machine as well as to provide feeding power to and counteract forces of reaction from the rock drill machine. Normally, the feed leg is with one end attached to the rock drill machine directly under said rock drill machine, while the other, opposite end is configured with e.g. a foot by means of which the feed leg rests against the ground. The feed leg normally comprises a cylinder pipe, a piston, a piston rod, a control and means for feeding a compressed medium to and into the cylinder pipe on the respective side of the piston therein. Depending on which side of the piston the pressure medium is fed, the piston rod is driven out of or into the cylinder pipe. The feed leg can be pneumatically or hydraulically operated. The control for the feed leg is traditionally located directly on the feed leg, but there are other solutions, and a starter for the rock drill machine is found on top thereof, which means that one can not reach the controls without moving the hands therebetween.
At collaring, i.e. when drilling of a hole is started, one has to control the feed leg and smoothly start the rock drill machine while you at the same time lift the rock drill machine for positioning the drill. This can be difficult to do with the control for the feed leg and the starter for the rock drill machine at a distance from each other.